Rainbow trout

Quick facts

How to identify it

A streamlined salmonid with a small head, a broad pink to red band along the flank and a dense sprinkling of small black spots over the back, dorsal fin, adipose fin and the whole tail. The back is steel-blue to olive-green, the belly silvery white, and the gill covers often carry a rosy flush. The spotted tail is the quickest way to tell it from the brown trout, which has an almost unspotted tail and red spots ringed with pale halos. Brook trout and Arctic char have light spots on a dark body and white-edged fins, which the rainbow never shows. Freshly stocked fish are pale and silvery; fish that have lived wild for a season darken and colour up.

Where it lives

Rainbow trout need cool, well-oxygenated water but tolerate warmer and slightly less pristine conditions than brown trout, thriving between roughly 10 and 18 °C. In rivers they hold in faster water than browns: the heads of pools, current seams beside riffles, below weirs and along undercut banks. In lakes and reservoirs they cruise open water and follow the wind, feeding near the surface in spring and autumn and dropping to the thermocline in summer. Across Europe most rainbows live where they were stocked — commercial put-and-take lakes, gravel-pit fisheries, reservoirs and managed river stretches — because they rarely reproduce successfully outside a few cold, spring-fed rivers.

Season and behaviour

Rainbow trout spawn in late winter and spring, generally from January to April, though many hatchery strains are bred to spawn in autumn, so stocked waters hold conditioned fish year-round. They feed actively in cold water, which makes them a genuine all-season target; the best fishing comes in spring from March to June, when insect hatches peak and the water is still cool, and again in autumn from September to November. In high summer the fish go deep or feed only in the early morning and at dusk. Overcast days, a ripple on the water and rising water after rain all improve sport, while bright sun and flat calm make lake fish wary. Rainbows are opportunists, chasing insects, fry and anything that flashes.

Fishing methods

Fly fishing is the classic approach: dry flies and nymphs during hatches in rivers, and lures, buzzers and small streamers on floating or intermediate lines in lakes, retrieved with a steady figure-of-eight or short strips. Ultralight spinning is just as effective and often more practical — small spinners, 2–5 g spoons and 3–5 cm plugs cast and retrieved across current seams or along drop-offs, with a pause that often triggers the take. On commercial trout lakes the bombarda (sbirolino) float lets you present a fly, paste or worm far out at any depth, and a simple running ledger or waggler float with bait covers the rest. Use a light rod rated for 1–10 g, 0.16–0.22 mm mono or a fine braid with a fluorocarbon leader, and keep hooks small and sharp; barbless hooks make releasing fish easy.

Baits and lures

Rainbow trout take almost anything that looks alive or edible. Natural baits — earthworms, maggots, mealworms and sweetcorn — are the standard on put-and-take lakes, and floating trout paste or dough presented just off bottom is a proven stocked-fish bait. For lures, silver, gold and copper blades and spoons work in clear water; orange, pink and chartreuse patterns score in coloured water or on fresh stockies. In rivers, match the hatch with sedge, mayfly and olive imitations, and fish egg patterns and small streamers in cold water.

Tips from the bank

1. 01Fish the windward shore of a lake — the wind pushes food and warm surface water there and the trout follow.
2. 02Vary the retrieve until you find what works: stocked rainbows often want a fast, erratic lure, wild fish a slow one.
3. 03Pause the spoon or spinner for a second mid-retrieve; the flutter on the drop triggers following fish.
4. 04On rivers, fish the faster water at the head of pools that brown trout usually ignore.
5. 05Use a fluorocarbon leader of 0.18–0.22 mm in clear water — rainbows become line-shy after they have been caught and released a few times.
6. 06Carry a landing net and unhook fish in the water; rainbows thrash and shed hooks on the bank.
7. 07In summer fish at first light or after sunset, when the surface layer cools.

Where to catch Rainbow trout

Waters where Shoalmap's fishing reports list Rainbow trout.

• Grauklingenbach
• Kuka
• Montour Run
• Lake Rhea
• Fosso Vorga
• Arroyo de Valbueno

Related species

• Brown trout
  Salmo trutta

  The wary, spotted native of cold rivers and deep lakes.

• Brook trout
  Salvelinus fontinalis

  The jewel-coloured char of icy headwaters and mountain lakes.

• Sea trout
  Salmo trutta trutta

  The silver, sea-going brown trout that runs the rivers at night.

• Grayling
  Thymallus thymallus

  The sail-finned lady of clean, fast-flowing rivers.

Frequently asked questions